The scientist failed in his experiments many a time, but he was never ____; instead, he stuck it out and finally made a great scientific discovery.
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When I asked my mother if I could marry George, she ____but rather unwillingly.
The garden has fallen into a state of ____since its owner died two years ago.
Coming home late, the boy ____quietly into the house to avoid waking his parents.
If you want to learn a language well, ____time is necessary.